The world begins two final days of mourning for Muhammad Ali on Thursday when the boxing great will be honoured with a Muslim funeral a day before receiving a final goodbye with an interfaith service.

Muhammad Ali's hometown of Louisville will honour the former boxing champion on Friday with a procession through the Kentucky city and public funeral at a sports arena, a tribute befitting a local hero who achieved global stature as a humanitarian.

The death of Muhammad Ali, the former heavyweight champion known as much for his political activism as his boxing brilliance, triggered a worldwide outpouring of affection and admiration for one of the best-known figures of the 20th century.

More than 60 years ago, a bicycle thief in Louisville, Kentucky, unknowingly set in motion one of the most amazing sports careers in history.

'In the newsroom, the thought process is about understanding the story and trying to look beyond the obvious. The fiction-writing process is similar in many ways but more internal.'